|
software keywords |
Description Developed by Nantucket software and released in winter of 1984, first shipping 25 May 1985 [4]. Clipper was a typical database development language and DOS based.
Originally is was used as a replacement programming language for Ashton
Tate's DbaseII database environment that could be compiled and executed
as a standalone application. One of the language's features: the possibility to link 'C' and machine language objects made it a virtual unlimited expandable environment. When you missed a feature, an interface or whatever you could program that yourself and the extension made a reusable part of your toolbox. Libraries were also made by third parties but the programmer could also create its own library or enhance the existing ones. One of the disadvantages, for commercial developers at least, was that a clipper executable could easily be disassembled or de-compiled to produce native source code. There were even commercial packages for that. Between the manufacturers of decompilers and Clipper a covenant was agreed that with a certain code in the source the decompilers would not decompile. But for the hard core hackers no door was kept close. Around the early 1990's the users felt a need for a more object oriented environment. Nantucket's answer was: Clipper 5.0 up to 5.3. This made the Clipper language more sophisticated, but completely OO it never was. Objects and classes could be created but the language needed more, and quickly, should it keep its programmers corps it had created since 1984. Too late the Nantucket company realized it had to port the Clipper
environment to the Windows platform as well. Too late, or at least
the research was not given top priority for research and development.
In August 1994 (Shipped December 1995 [4]) a first
version became available and was called: Clipper VO (virtual objects)
It was truly windows based but had to cope with many typical first
issue bugs that were not explained to the full extend. Again programmers
had to build new work arounds and did not feel very comfortable with
that idea. Though Nantucket / CA promised a high degree of compatibility with older developments this did not materialize to the degree to make life easier to former Clipper programmers. The result was that programs were rebuilt in the new environments, the best way to do porting actually. Again slimming down the market for Clipper programmers. In 1995 Computer Associates bought up the Clipper environment, killed
the Clipper DOS version and further developed VO. It seemed that CA
again did not realize the full potential of Clipper VO and undercut
its marketing budget. Thus VO 2.5 is the latest version since 1997
Some of the most eye catching features of VO:[2]
Other developments for Clipper: Clipper also could be converted to run on UNIX systems by using a porting tool called Flagship. It runs suitably well. XBase++ is an OO environment and translates DOS Clipper to Windows but does not enhance the clipper development to an event driven application Clip-4-Win is a 16 bit compiler and generated character based applications that ran fairly well within Windows.
Clipper Revisited (contributed by Götz Strehl) Clipper got a new life with the Harbour project. The harbour-project was started as an open source project in early 1999, the project is still on, but not updated since late 2003.(6) Out of the harbour-project, xHarbour (extended Harbour) was started by Ron Pinkas late 2001 as a fork off of the Harbour Project in which he was one of the leading developers. xHarbour was established to provide a more aggressive alternative to the conservative style of development in the Harbour Project. This project is up to date and in development until today.(7) At the end of December 2002, Ron Pinkas
and Patrick Mast discussed the idea to establish
a corporation, aiming to give xHarbour its appropriate place in main
stream development tools, much like Clipper at its high time.
The corporation was registered on January 30 2003, in the state of
Nevada U.S., as "xHarbour.com
Inc.".
The xHarbour programming language is a superset of the well known
xBase language, often referred to as Clipper. xHarbour is 100% backward
compatible with the Clipper Language, yet it adds many modern features
and tools comparable to today’s leading compilers. Such features
include Visual xHarbour (IDE), SQLRDD, xBuild Project Wizard, ActiveX,
OLE, RMDBFCDX ( Comix / Clipmore compatible super fast filters),
and many more.(8) Clipper is still alive!
|
![]()
| Last Updated on July 30, 2006 | For suggestions please mail the editors |
Footnotes & References